Dried lima beans, with a ham hock in a Dutch oven.....with a small onion chopped, and about 1/2 a carrot, grated.
Cover and cook very slowly until the beans are just tender....about 1 1/2 to 2 hours.
Then salt and pepper to taste.....depends on how salty the ham is.
If your lid doesn't fit well, you may have to add water to keep it from drying out.... And if your ham isn's sweet smoked you may want to add about a tsp fo sugar......and lots of people like thyme in limas....I don't often add it....
I suspect you cooked them too long and allowed them to dry out.
Linda C

You probably need to do an overnight soak with the beans. I know folks like to try to skip this step, but it truely makes a difference in the quality of the finished food.